COVID-19 pneumonia with Fontan-circulation that resulted in circulatory collapse and hypoxemia due to high PEEP

We read the article by Chavez et al. with great interest and appreciate the authors' efforts to provide resuscitation strategies and airway management techniques in patients with COVID-19 for emergency medicine clinicians [1]. Chavez et al. recommend treating intubated COVID-19 patients with ARDS with higher PEEP than lower PEEP as in other ARDS.

However, we are concerned about their discussion, specifically, that high PEEP for patients with Fontan circulation is contraindicated after intubation for COVID-19 pneumonia with ARDS [2].

We experienced a case of a young man in his 20s with COVID-19 pneumonia who underwent high PEEP after intubation, which resulted in a circulatory collapse and severe hypoxemia that was barely saved by VA-ECMO. It was later determined that the patient had Fontan circulation.

A young man in his 20s visited our emergency department complaining of nasal discharge, general malaise, coughing for four days prior to the visit, and a fever of 39 °C and headache that began the previous day. He did not report dyspnea. The patient's medical history included surgery for a ventricular septal defect, pulmonary artery stenosis, and transposition of the great vessels, and he visited a cardiology department at another hospital annually. However, at the time of the patient's visit, he was unaware that he had Fontan circulation. The patient had not received COVID-19 vaccination.

On the presentation, vital signs were as follows: clear consciousness, temperature 38.0 °C, respiratory rate 16 breaths/min, and SpO2 86–89% in the ambient air, although the usual SpO2 was unknown. Physical examination revealed a surgical scar on the midline of the anterior thoracic region and clubbed fingers on the hands and feet. The nasopharyngeal swab was positive for COVID-19 via the NEAR method. A chest x-ray showed ground glass opacities in bilateral lower lung fields.

However since SpO2 had not been usually measured during the patient's usual outpatient hospital visits, we requested medical information regarding the postoperative history of his congenital heart disease. Treatment was initiated with remdesivir and dexamethasone, as well as a subcutaneous injection of calcium heparin.

On the second day of hospitalization, oxygenation deteriorated, with a respiratory rate of 14–19 breaths/min and SpO2 of 9196% (O2 4–5 L/min), which did not improve in the supine position.

Even with nasal high flow(flow rate: 40 L/min, FiO2: 70%) on the third day of hospitalization, SpO2 dropped to approximately 90%. Suspecting ARDS with COVID-19 pneumonia, an emergency intubation was performed. However, even just before the intubation, the patient did not complain of any dyspnea.

While SpO2 maintained approximately 80% after attaching to the ventilator (VCV mode: FiO2 100%, PEEP 5 cmH2O, RR 15 breaths/min, TV 500 mL), PEEP was gradually increased to 15 cmH2O. Chest x-ray performed immediately after intubation showed no evidence of pneumothorax or exacerbation of the pneumonia. Transthoracic echocardiography made it difficult to assess the cardiac structure and function in vivo.

Despite the application of higher PEEP, systolic blood pressure decreased below 80 mmHg, and SpO2 fell below 80%. The airway pressure was further increased manually with Jackson Reese breathing system, and noradrenaline was administered for hypotension, but the blood pressure continued to decrease. Urgently, VA-ECMO was inserted by cardiologists, and SpO2 and blood pressure improved. On the same day, the patient was transferred to a higher-level tertiary hospital due to unexplained hypoxemia and hypotension.

Subsequently, medical information obtained from the patient's usual cardiologist revealed that he had undergone total cavopulmonary connection (Fontan operation) for the left ventricular hypoplasia and the complete transposition of the great vessels in his childhood. The patient was successfully weaned from VA-ECMO a few days later and discharged without any sequelae.

Post-intubation high PEEP is contraindicated in patients with Fontan circulation due to their unique hemodynamics, in which the venous circulation returns directly to the pulmonary artery (Fig. 1 ), and high PEEP can easily disrupt the hemodynamics (Fig. 2 ).

Fig. 1.

Lateral tunnel Fontan operation for complete great vessel transposition (type III) and left ventricular hypoplasia.

Fig. 2.

In the Fontan circulation, high PEEP causes a decrease in venous return and cardiac output. Simultaneously, fenestration increases right-left shunt blood flow, resulting in hypoxemia.

Since the onset of the COVID-19 pandemic in 2019, the number of cases with Fontan circulation, who may be treated by internists, emergency physicians, infectious disease physicians, and intensivists, had likely increased. However, the risk associated with high PEEP for Fontan circulation is not widely known among these medical professionals.

In Japan, there is no portable medical information card available to illustrate the unique hemodynamics of patients with Fontan circulation. We proposed that the Japanese Society for Congenital Heart Disease recommends that postoperative patients with Fontan circulation obtain a “Fontan-circulation patient Card” (Fig. 3 ), which describes the precautions in the treatment of Fontan circulation [3].

Fig. 3.

Fontan circulation patient card.

In conclusion, Chavez et al. 's study is a valuable resource for emergency physicians. We believe that the study would be further strengthened by the addition of a cautionary note stating that the treatment of ARDS due to COVID-19 pneumonia with high PEEP is contraindicated for patients with Fontan circulation.

CRediT authorship contribution statement

Masashi Oe: Writing – original draft. Atsushi Shima: Writing – review & editing. Takeshi Ueda: Writing – review & editing.